How many bits must be borrowed from the host portion of an address to accommodate a router with five connected networks?

Hi!

The correct answer is 3 bits.

Explanation:

Each connected network needs a unique address.

If you borrow 3 bits from the host portion of an address then you have a combination of:

.000

.001

.010

.011

.100

.101

.110

.111

The borrowed address from the host portion, in this case, are 2³ = 8 address, this means that you have 3 address left before needing more bits.