Explanation:

- The sentence in question uses "was living." However, since the action started in the past and continues to the present, a different tense is more appropriate.

- Option 1: "has been living"

- ?? This is the present perfect continuous tense, which is used for actions that began in the past and continue in the present.

- Correct: "Manoj has been living in the city since 1993."

- Option 2: "No substitution required"

- Incorrect as it implies the original tense is proper, but it doesn't convey the ongoing nature of the action.

- Option 3: "is living"

- This is the present continuous tense, implying a current action, but it doesn't convey the duration starting from 1993.

- Option 4: "will be living"

- This refers to a future action, irrelevant for actions starting in the past.