Which of the following is an example of an unsaturated fatty acid?

Which one of the following structural formulae of two organic compounds is correctly identified along with its related function?

The sources of fats and oils are:

Sterone and sterol are distinguished based on the presence or absence of which group?

Read the following statements on lipids and find out the correct set of statements:
$(a)$ Lecithin found in the plasma membrane is a glycolipid.
$(b)$ Saturated fatty acids possess one or more $C=C$ bonds.
$(c)$ Gingely oil has a lower melting point,hence remains as oil in winter.
$(d)$ Lipids are generally insoluble in water but soluble in some organic solvents.
$(e)$ When fatty acid is esterified with glycerol,monoglycerides are formed.
Choose the correct answer from the options given below:

Oleic acid is an example of ........