Concept:  The question tests on framing and solving simultaneous linear equations

Solution:

Let the number of horses = h and the number of pigeons = p

h + p = 80 ... (1)

4h + 2p = 260 ... (2) From (1), we get p = 80 - h. putting this in (2), we get 4h + 2(80 - h) = 260

4h + 160 - 2h = 260

2h = 100

h = 50

Option C