Multiple choice

 This environment has extremely salty water. It is the  _____________. 

  1. Estuary

  2. Pond

  3. Ocean

  4. River

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Oceans contain saltwater with high salinity levels, unlike freshwater ponds and rivers. Estuaries contain brackish water, which is a mix of fresh and salt water, but not as consistently salty as the open ocean.