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MODEL PAPER 4 — BIOLOGY STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceBIOLOGYMODEL PAPER 41 Mark
MCQ
Assertion (A): Evolution is a continuous process that takes millions of years for speciation.
Reason (R): During evolution, small variation accumulates guided by natural selection that leads to speciation.
  • A
    Both A and R are true and R is the correct explanation of A.
  • B
    Both A and R are true but R is not the correct explanation of A.
  • C
    A is true but R is false.
  • D
    A is false but R is true.
✓

Answer

(a) : Both A and R are true and R is the correct explanation of A.
Explanation: Evolution is a slow and continuous process that takes a long time to form a new species. Variation due to mutation, genetic drift, geographical isolation leads to speciation.

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