Fermentation is a metabolic process that converts sugar to acids, gases or alcohol. It occurs in yeast and bacteria, and also in oxygen-starved muscle cells, as in the case of lactic acid fermentation.

Pasteurization is the technique of heating milk at a high temperature ( 75$^0$ C) for a short period of time (15 s) and again cooling down quickly. It kills bacteria that may be in the milk, to ensure its safe consumption. Also, it increases the lifespan of milk. Therefore, pasteurisation is a 'sterilisation technique'.

Phenol usually in low concentrations is used in household used for cleaning and disinfecting purpose.Chloroform can't be used for disinfecting utensils as it is an anesthetic drug and causes dizziness.Isopropanol is a flammable reagent and also can't be used as a cleaning product.Butanol is usually used in painting or other work as thinner and also its fumes are harmful if inhaled and may cause slight irritation. so this also can't be used for disinfecting utensils. So, the correct answer is'5% of phenol'

The yeast is a type of fungal species which have unicellular cells. These cells are known to perform anaerobic fermentation of the sugars and produce alcohol and carbon dioxide. The organism respires anaerobically and breaks down the fermentable sugars in the absence of oxygen.

Gamma rays are used for sterilization of pharmaceutical products after their production as to prevention the growth of any microorganism that may be present in the product. It is also used for sterlization of food product to kill any harmful bacteria or other organism that are present in the food, it won't make the food radioactive. Gamma rays act as a ionising radiation and it will inhibit the growth of microorganism. So it can be used to sterilize culture media. So, the correct answer is 'Both A and C'

Hops used to provide a distinct flavour to beer are actually the flowers of Humulus lupulus

Aseptic culture means culture which takes place in the absence of harmful microbes or other contaminants. During tissue culture, the cells are kept under the aseptic condition to avoid contamination caused by microbes because the microbes inhibit the growth of the cell and utilize the nutrients provided for the plants in the media for their growth as they have the ability to multiply fast. The aseptic condition during culture can be maintained by the process of heating, fumigation of lab, autoclave apparatus before use, wiping the apparatus with alcohol, performing the experiment in the laminar air flow under HEPA filters. 

Zymase is the enzyme complex that catalyse the fermentation of sugar into ethanol and $CO _2$. It occur naturally in the yeast. Zymase activity varies as among the yeast strains.

It is important to boil surgical instruments before using them in an operation. It is done to kill all the pathogens which may be infecting the instruments. After the operation and surgery, the germs and pathogens are present on the instruments used during operation and surgery. So in order to kill those pathogens and bacterial cyst, the surgical instruments are boiled for 10 to 15 minutes. This will reduce the risk of transmission of disease from one person to another person.

Yeast is a fungal species that converts carbohydrates to carbon dioxide and alcohols. Saccharomyces cerevisiae is responsible for the production of ethyl alcohol.

Making beer, wine, cheese, curd etc using microorganisms are classic methods of biotechnology I.e. using microbes for isolation. Of product of our use. While with advancement in technology, we have extended biotechnology to other purposes like Cleaning up oil spills, increasing soil fertility, obtaining minerals from mining etc. 

Adaptation is the alteration in the structure or function of an organism or any of its parts that results from natural selection and by which the organism becomes better fitted to survive and multiply in its environment. The bacteria got adapted towards the changes and hence survived.

Tissue culture is the growth of cells or tissues separated from an organism. This is facilitated using a liquid, semi-solid medium which is sterilized so as to prevent the contamination by autoclaving them. It is a process whereby applying heat and pressure, microbes are killed in a container.

Saccharomyces cerevisiae (common yeast) is a species of yeast. It is the most useful yeast, linked to wine making, baking and brewing. It is also called as baker's yeast or brewer's yeast.

A) Viruses inhibit the growth of other organisms by entering the host organism and using its genetic material and nutrition to reproduce. Hence, the fungus stops growing.

Fungi are a separate class of microorganisms that reproduce by spores and are thus different from plants that require photosynthesis to make food for themselves. Fungi consist of molds, yeast, mildew, and mushrooms. It can be unicellular or multicellular. So all mushrooms are fungi, though not all fungi are mushrooms as there are much more types of fungi than mushrooms. Mushroom is not yeast.

Pre T cells are progenitors of T- lymphocytes which are produced from the bone marrow. Pre- T cells undergo differentiation and maturation in the thymus to form matured T- cells. T-cells can be distinguished from other lymphocytes by the presence of a T-cell receptor on the cell surface.  Hence, Progenitors formed in bone marrow but differentiating elsewhere are Pre-T cells.