Which of the following socket types is for an Intel CPU?

Socket F (also called Socket 1207) is an AMD server socket used for Opteron processors, not an Intel socket.

Socket 940 is an AMD socket used for Opteron and early Athlon 64 FX processors and is not associated with Intel CPUs.

AM3 is an AMD consumer desktop socket used for Phenom II, Athlon II, and Sempron processors and is incompatible with Intel CPUs.

LGA 1156 is an Intel Land Grid Array socket introduced in 2009 for the Intel Lynnfield and Clarkdale microarchitectures, supporting Core i3/i5/i7 processors. The '1156' refers to the 1156 contact points on the motherboard socket that interface with the CPU. Intel uses LGA (Land Grid Array) sockets where the pins reside on the motherboard, not the CPU.