The correct option to fill in the gaps in the sentence “Someone … the radio cassette since 6 p.m. I wish he … turn it off” is A. has been playing/ would. So, the completed sentence is: “Someone has been playing the radio cassette since 6 p.m. I wish he would turn it off.”

Here’s why:

• A. has been playing/ would: This is the correct option. “Has been playing” is used to describe an action that started in the past and is still happening now. “Would” is used to express a polite request or wish.

• B. is playing/ would: This option is incorrect because “is playing” is used for actions happening right now, not actions that started in the past and are still happening now.

• C. played/ will: This option is incorrect because “played” is used for actions that happened and finished in the past, not actions that started in the past and are still happening now. “Will” is used to talk about future actions, not to express a wish or request.

• D. has played/ should: This option is incorrect because “has played” is used for actions that happened and finished at an unspecified time in the past, not actions that started in the past and are still happening now. “Should” is used to give advice or suggestions, not to express a wish or request.

• E. plays/ will: This option is incorrect because “plays” is used for habitual actions, not actions that started in the past and are still happening now. “Will” is used to talk about future actions, not to express a wish or request.