Consider the following statements:
Assertion $(A)$: The direction ratios of a line $L_1$ are $2, 5, 7$ and the direction ratios of another line $L_2$ are $\frac{4}{\sqrt{19}}, \frac{10}{\sqrt{19}}, \frac{14}{\sqrt{19}}$. Then the lines $L_1, L_2$ are parallel.
Reason $(R)$: If the direction ratios of a line $L_1$ are $a_1, b_1, c_1$,the direction ratios of a line $L_2$ are $a_2, b_2, c_2$ and $a_1 a_2 + b_1 b_2 + c_1 c_2 = 0$,then the lines $L_1, L_2$ are parallel. Which one of the following is true?

  • A
    $(A)$ and $(R)$ are true. $(R)$ is the correct explanation of $(A)$
  • B
    $(A)$ and $(R)$ are true,but $(R)$ is not the correct explanation of $(A)$
  • C
    $(A)$ is true,$(R)$ is false
  • D
    $(A)$ is false,$(R)$ is true

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