P3 Sketcn
By Carl Sandburg
The shadows of the ships
Rock on the crest
In the low blue lustre
Of the tardy and the soft in rolling tide.
A long brown bar at the dip of the sky
Puts an arm of sand in the span of salt.
The lucid and endless wrinkles
Draw in, lapse and withdraw.
Wavelets crumble and white spent bubbles
Wash on the floor of the beach
Rocking on the crest
In the low blue lustre
Are the shadows of the ships,
How is imagery used in this poem

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.

c is the answer because first she would blush to make the reader wonder why which they find out in the next line.