Concept:
The Supreme Court can issue writs under Article 32 for the protection of Fundamental Rights.
Step 1:
Habeas Corpus is issued to produce a detained person before the court.
\[
A \text{ is correct}
\]
Step 2:
Mandamus orders a public authority to perform its duty.
\[
B \text{ is correct}
\]
Step 3:
Functionalist is a sociological perspective, not a writ.
\[
C \text{ is incorrect}
\]
Step 4:
Prohibition prevents lower courts from exceeding their jurisdiction.
\[
D \text{ is correct}
\]
Step 5:
Thus, the correct combination is:
\[
A,\ B,\ D \text{ Only}
\]
\[
\boxed{\text{(2) A, B, D Only}}
\]