At mid-day in the summer, what would be the best choice in attempting to communicate, using NBDP with a shore station some 1800 miles distant?

Correct Answer: Option B — Higher HF bands

For an 1800-mile distance during mid-day, high-frequency sky wave propagation is required. Higher HF bands are necessary because the intense solar radiation during mid-day increases ionospheric ionization, requiring higher frequencies to ensure the signal reflects off the ionosphere rather than being absorbed by the D-layer.