funcf(x) + funcg(x)
$funcf$ or $funcg$ can be executed first as whether the first operand or the second operand to '+' operator is first executed is not defined in C language and it depends on the compiler implementation. But here the order does not matter as both the operands are not affecting each other and '+' is commutative. Lets assume $funcf$ is executed first. It calls $funcg$ - so even if the order of call is reversed, result will be same.
In first call of $funcg$, $y$ becomes $11$ and it returns $5+11 = 16$.
In second call of $funcg$, $y$ becomes $12 $ and it returns $5+12 = 17$.
So, in main $y$ is incremented by $16+17 = 33$ to become $10+33 = 43$. (Choice A)
In the second iteration $y$ will be incremented by $18+19 = 37$ to give $43+37 = 80$.