Answer: E

Response:

$1,236.94 = $50 {[1 – 1/(1 + R)28] / R} + 1,000 / (1 + R)28; R = 3.637%; YTM = 3.64% x 2 = 7.27%

The algebra is a bit annoying, so do the TVOM stuff, thusly: -1,236.94PV, 1000 FV, 28 N, 50 PMT, CPT I/Y = 3.637. I/Y x 2 = 3.637 x 2 = 7.274 or 7.27%