All are compounds except Br2 (because it is a di-atomic molecule.
A compound is two or more different elements chemically combined together.
Zn + SO4 are two different elements chemically combined together.
Rb + Cl are two different elements chemically bonded together
C + H4 are two different compound chemically bonded together by covalent bond
So, statement 3 "BR2 + CH4" are wrong. The remaining are correct