Choose the grammatically correct sentence from the given options:

The correct answer is Option (4) → The book contains good aptitude based questions.

Stative verbs:

• A stative verb describes a state or a condition, not an action: contain, own, belong, know, consist.
• Stative verbs are normally not used in the continuous tenses (be + verb-ing).
• This sentence: "contain" states a fixed fact about what is in the book, so the simple present "contains" is correct.
  Example: This bottle contains one litre of water.

Why the Other Options are Incorrect?

Option 1: The book is containing good aptitude based questions. — Incorrect. "Is containing" puts the stative verb into the present continuous; the correct form is "contains".
Corrected: The book contains good aptitude based questions.

Option 2: The book was containing good aptitude based questions. — Incorrect. "Was containing" puts the stative verb into the past continuous; even for the past, the form would be "contained".
Corrected: The book contained good aptitude based questions.

Option 3: The book will be containing good aptitude based questions. — Incorrect. "Will be containing" puts the stative verb into the future continuous; the form would be "will contain".
Corrected: The book will contain good aptitude based questions.

Contrast: action verbs (read, write) can take be + -ing; stative verbs (contain, own, know) stay in the simple tenses.