has eaten will replace ate because –
Since is used with the Present/Past Perfect Tense that indicates a time from the past until a later past time, or until now
Look at the examples given below :
I haven’t eaten since breakfast.
He has been working in a bank since leaving school.
Hence, He has eaten is the right usage

Correct Option: A

has eaten will replace ate because –
Since is used with the Present/Past Perfect Tense that indicates a time from the past until a later past time, or until now
Look at the examples given below :
I haven’t eaten since breakfast.
He has been working in a bank since leaving school.
Hence, He has eaten is the right usage

that will not be used because –
Interrogative sentences with wh, or Q.wds. when changed into Indirect speech, no Conj. will be used.
Look at the examples given below :
He said, “What are you doing here ?” (D.S.)
He asked what I was doing there. (I.S.)
She said, “Where are you going ?” (D.S.)
She asked where I was going. (I.S.)
Hence, how long will replace that how long

Correct Option: B

that will not be used because –
Interrogative sentences with wh, or Q.wds. when changed into Indirect speech, no Conj. will be used.
Look at the examples given below :
He said, “What are you doing here ?” (D.S.)
He asked what I was doing there. (I.S.)
She said, “Where are you going ?” (D.S.)
She asked where I was going. (I.S.)
Hence, how long will replace that how long

into will replace out of because –
take the law into your hands (Idiom) : to do something illegal in order to punish somebody for doing something wrong, instead of letting the police deal with him
Look at the examples given below :
Citizens don’t have the right to take the law into their own hands.
The shopkeeper took the law into his own hands
when he tried to arrest the thief.
Hence, into their hands is the right usage.

Correct Option: C

into will replace out of because –
take the law into your hands (Idiom) : to do something illegal in order to punish somebody for doing something wrong, instead of letting the police deal with him
Look at the examples given below :
Citizens don’t have the right to take the law into their own hands.
The shopkeeper took the law into his own hands
when he tried to arrest the thief.
Hence, into their hands is the right usage.

No error

Correct Option: D

No error

punishable will replace punished because –
punishable (Adj.) : that can be punished, especially by law
punish (Verb) : to make somebody suffer because he has disobeyed the law or done something wrong
Look at the examples given below :
He was punished for refusing to answer their questions.
Giving false information to the police is a punishable offence.
Hence, a punishable offence is the right usage

Correct Option: C

punishable will replace punished because –
punishable (Adj.) : that can be punished, especially by law
punish (Verb) : to make somebody suffer because he has disobeyed the law or done something wrong
Look at the examples given below :
He was punished for refusing to answer their questions.
Giving false information to the police is a punishable offence.
Hence, a punishable offence is the right usage