Correct option is D
1. Line 1: x 1 = y 2 = z 3 Direction vector ( d 1 ⃗ ) : d 1 ⃗ = ( 1 , 2 , 3 ) Point on the line ( P 1 ) : ( 0 , 0 , 0 ) 2. Line 2: x − 3 − 3 = y − 4 − 6 = z − 5 − 9 Direction vector ( d 2 ⃗ ) : d 2 ⃗ = ( − 3 , − 6 , − 9 ) Point on the line ( P 2 ) : ( 3 , 4 , 5 ) Check if the Direction Vectors are Scalar Multiples d 2 ⃗ = − 3 ⋅ d 1 ⃗ ( − 3 , − 6 , − 9 ) = − 3 ⋅ ( 1 , 2 , 3 ) Since d 2 ⃗ is a scalar multiple of d 1 ⃗ , the lines are parallel . \begin{aligned}&\textbf{1. Line 1:} \\&\quad \frac{x}{1} = \frac{y}{2} = \frac{z}{3} \\&\quad \textbf{Direction vector } (\vec{d_1}): \vec{d_1} = (1, 2, 3) \\&\quad \textbf{Point on the line } (P_1): (0, 0, 0) \\\\&\textbf{2. Line 2:} \\&\quad \frac{x - 3}{-3} = \frac{y - 4}{-6} = \frac{z - 5}{-9} \\&\quad \textbf{Direction vector } (\vec{d_2}): \vec{d_2} = (-3, -6, -9) \\&\quad \textbf{Point on the line } (P_2): (3, 4, 5) \\\\&\textbf{Check if the Direction Vectors are Scalar Multiples} \\&\quad \vec{d_2} = -3 \cdot \vec{d_1} \\&\quad (-3, -6, -9) = -3 \cdot (1, 2, 3) \\\\&\text{Since } \vec{d_2} \text{ is a scalar multiple of } \vec{d_1}, \text{ the lines are } \textbf{parallel}.\end{aligned} 1. Line 1: 1 x = 2 y = 3 z Direction vector ( d 1 ) : d 1 = ( 1 , 2 , 3 ) Point on the line ( P 1 ) : ( 0 , 0 , 0 ) 2. Line 2: − 3 x − 3 = − 6 y − 4 = − 9 z − 5 Direction vector ( d 2 ) : d 2 = ( − 3 , − 6 , − 9 ) Point on the line ( P 2 ) : ( 3 , 4 , 5 ) Check if the Direction Vectors are Scalar Multiples d 2 = − 3 ⋅ d 1 ( − 3 , − 6 , − 9 ) = − 3 ⋅ ( 1 , 2 , 3 ) Since d 2 is a scalar multiple of d 1 , the lines are parallel .