Subnet Mask = 255.255.255.192
If we only write the last byte into binary, then we get,
255.255.255.11000000
∴ Number of 0's in subnet mask = Number of bits in host ID = 6
∴ Maximum number of hosts = 2^ (Number of bits in host Id) - 2 [since the 1st and last IP address is used for Network ID and Directed Broadcast Adddress]
= 2^6 - 2
= 64 - 2
= 62
Option (c) is the right answer