He harvested a rich crop from that fecund land.

Obsolete means no longer used or relevant.

Barren means not producing anything.

Fruitless means not producing any fruit.

In the sentence “He harvested a rich crop from that fecund land,” the word “fecund” means fertile. This is because the land is producing a rich crop, which is a sign of fertility. The other options are not correct because they do not describe the land as being good for growing crops.