Help to selectively choose condition in EA

I built this EA that opens trades following a serious of conditions:

ConditionA && ConditionB && ConditionC && ConditionD

now i wanted to be able to selectively choose the conditions in the EA's inputs.

this was my solution:

replacing ConditionA for ContinonAEnabled
creating a extern bool for it
and : If ConditionAEnabled (ConditionA); else NULL;

i get no errors or warning but it didn't work. I'm new to coding, my question is what can i use, instead of NULL, if i want to ignore ConditionA.
If i don't use ConditionA i still got to put something there.
Or is the way i'm approaching this problem all wrong?

You don't need "else NULL;" ConditionA will be ignored if ConditionAEnabled is false
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