What term describes a feature on the Earth's surface that includes formations such as headlands or beaches?

The term that describes features on the Earth's surface including formations like headlands or beaches is "coastal landform." Coastal landforms are shaped by the processes of erosion, deposition, and longshore drift, created by the interaction of the land with oceanic and atmospheric forces. Headlands are typically formed where harder rock is more resistant to erosion, protruding into the sea, while beaches are formed from the accumulation of sand and pebbles along the shoreline through the deposition of materials transported by waves.

In contrast, the other terms represent different types of geographic features. A river delta refers to sediment deposits at the mouth of a river where it meets a body of water, typically creating a fan-like shape. A coral reef is a marine structure formed by the accumulation of coral organisms, found in tropical coastal waters, but does not include formations like headlands or beaches. A mountain range is a series of mountains connected together, often formed by tectonic activity and is not related to coastal processes. Therefore, "coastal landform" is the most accurate term in this context.