What is the total number of $\pi$ bonds in the compound $CH_2=CH-CH=CH-COOH$?

$\pi$ bond is formed by:

Given below are two statements: One is labelled as Assertion $A$ and the other is labelled as Reason $R$.
Assertion $A$: Zero orbital overlap is an out-of-phase overlap.
Reason $R$: It results due to different orientation/direction of approach of orbitals.
In the light of the above statements,choose the correct answer from the options given below.

Explain $\sigma$ bond formed by $s-s$,$s-p$ and $p-p$ overlapping.

Which of the following statements is $NOT$ correct?

The double bond between the two carbon atoms in ethylene $(CH_2=CH_2)$ consists of: