Which term means "trench" or "gutter" in 18th century French, referring to a strait between Lake Pontchartrain and the Gulf of Mexico?

The term that means "trench" or "gutter" in 18th-century French and refers to the strait between Lake Pontchartrain and the Gulf of Mexico is indeed The Rigolets. This geographic feature is crucial in the context of New Orleans, as it serves as a natural channel connecting the freshwater Lake Pontchartrain with the saltwater Gulf of Mexico. The name 'Rigolets' directly translates to a smaller channel or stream, which accurately describes this waterway's role in the region's hydrology and contributes to the systems of trade and transport historically significant to New Orleans.

The other options do not refer to the strait between these two bodies of water. For instance, Lake Pontchartrain is the lake itself, while Rampart Street and Carondelet Street are notable streets in New Orleans, with neither having to do with the specific waterway described in the question. Understanding these geographic terms is important for grasping the historical and cultural context of New Orleans, especially as they relate to the city's development and its relationship with the surrounding bodies of water.