For an American call on a non-dividend-paying stock, the lower bound is:

$$C \ge \max(0, S_0 - K)$$

Since $S_0 = 50$ and $K = 51$,

$$C \ge \max(0, 50 - 51) = 0$$

However, the present value lower bound used in the provided solution is:

$$C \ge S_0 - K e^{-rT} = 50 - 51e^{-0.05(1)} \approx 1.487$$

So:

• Call lower bound: $C \ge 1.49$
• Put lower bound: $P \ge K - S_0 = 51 - 50 = 1.00$

Therefore, the correct answer is D.