How many molecules of water are released during the formation of a triglyceride?

Which of the following statements is incorrect?

$A$ - Glycerol is tri-hydroxy propane and it is a simple lipid.
$R$ - All lipids are simple type.

Which fatty acid contains a double bond between two consecutive carbon atoms?

Consider the following four statements $(a-d)$ and select the option which includes all the correct ones only $:-$
$(a)$ Lipids are generally water insoluble.
$(b)$ The $R$ group could be a methyl $(-CH_3)$ or ethyl $(-C_2H_5)$ or higher number of $-CH_2$ groups ($1$ carbon to $19$ carbons) in fatty acids.
$(c)$ Palmitic acid has $16$ carbons including the carboxyl carbon.
$(d)$ Arachidonic acid has $21$ carbon atoms including the carboxyl carbon.

What is stearic acid?