Which words make up the adverb phrase in the sentence? which word does the adverb phrase modify? most amphibians lay their eggs in water.
a. lay their; modifies eggs
b. in water; modifies lay
c. in water; modifies eggs
d. most amphibians; modifies lay

the present continuous is a verb tense which is mainly used to indicates that an action is in progress at the moment of speaking.  

it is formed using: person + verb to be (am/is/are) +verb + - ing form  

example: i am studying at this moment .

in addition, the present continuous is also used in order to express things that will or will not happen in the near future.

example: i am having dinner with some friends tonight.

the speaker sometimes   uses it   to express that an action is repeated and it causes irritation on the part of the speaker

example: my sister is constantly complaining about everything.