Answer:
Option A, accumulate sulfur as intracellular granules.
Explanation:
Purple sulfur bacteria belong to the group of Proteobacteria. These probacterias are anaerobic in nature and yet are able to photosynthesise. They are usually found in water environments such as hot springs, stagnant water etc. They use sulphur (either in the form of sulfide, or thiosulfate) as an electron donor in their photosynthetic activity to oxidise sulfur thereby producing granules of elemental sulfur.
while filamentous sulfur oxidizers use nitrate instead of oxygen to oxidize sulfide thereby producing granules.
Hence, option A is correct.
Convection Current
This happens when there is a noteworthy contrast in temperature between two sections of a liquid. At the point when this temperature distinction exists, hot liquids rise and cool liquids sink, and after that streams, or developments, are made in the liquid
Answer:melanism
Explanation:albino is when an animal has no melanin, which is the chemical that causes pigment (color). Melanism is when an animal has too much melanin and is completely black. That animal is melanistic.
Functions. this is the very idea behind differentiation.<span />
Answer:
Option A, a compound that contains carbon atoms bound to other elements
Explanation:
An organic compound is one which has at least one carbon atom that is bonded to several other atoms (may be metallic or non metallic) by a single or double bond is termed as organic compound . The most common atoms with which carbon forms bond are hydrogen, nitrogen,and oxygen.
Some common examples are -
Methane - 
Methanol - 
Hence, option A is correct