Hello!
The answer is:
The correct option is
a)

Why?
Since a right triangle is formed, we can calculate the resultant force using the Pythagorean Theorem which states that:

Where,
c, is the hypothenuse.
a, is one triangle leg.
b, is the other triangle leg.
So, we are given the information:


So, calculating the resultant force (hypothenuse), we have:

Hence, the expression that would find the result velocity is:
a) [tex]Resultant=\sqrt{22^{2} +4^{2} }[/tex]
Have a nice day!