Question

Assertion :

Petrified fossils contain hard parts of organisms.

Reason: Moulds and casts lack the remains of organisms.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
• C. Assertion is correct but Reason is incorrect
• D. Both Assertion and Reason are incorrect

Answer 1

The correct option is B Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion

• Replacement of organic parts by mineral deposits is called petrification.

• Fossils formed through petrification are termed petrified fossils.

• These fossils consists of only the hard parts of extinct organisms.

• Moulds of hardened and fossilized mud that surrounded an extinct individuals have been found.

• In most cases, the buried individuals have been completely destroyed, but themoulds have retained true copies of their shapes.

• Sometimes, a mould is found with petrified fossil of the individual also.

Such fossils are termed as casts. So, the correct answer is 'Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion'.