Metalloids are elements that have both metal and nonmetal properties
A. LITTORAL ZONE is a freshwater ecosystem that is home to rooted plants.
Littoral zone is the shallow area of a lake, pond, river or ocean. This is the area where mangroves grow.
Some counties and water district identify littoral zones so that these zone will be planted with native plants. This is done for the purpose of having the plants purify the water and maintain a balanced ecosystems.
The answer is going to be Rubidium. hope that helped