Forming number c
You should choose one,

L is short for long int, which stands for long integer.

C and d are illegal and will not be considered.

Long integer is 4 bytes long,

Valid values are between-2147483648 ~ 2147483647.

It is stipulated that the short type is not longer than the int type and the long type is not shorter than the int type.

So for some systems, short=int=long is 32 bits, so b is wrong.

If the int type is 16, b is right.

But because there is no specified system, B is wrong.

What's more, there is an A in this question. So I can only choose a.