What explains how or why the evidence supports a claim?

Is there a passage or something to read to understand the question?

Explanation:Evidence acts as justification for the arguments given and tends to persuade the public to accept statements. Evidence comes in different kinds, and tends to vary from one academic field or subject of argument to another.They offer audiences a way to see the idea illustrated in a specific case in a public speech.

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.