Force on a positive charge aligns with electric field direction

Steps:

• Electric field $\vec{E}$ from Y points in the direction of force on a positive test charge.
• X is positively charged, so force $\vec{F} = q\vec{E}$ (with $q > 0$) is in the same direction as $\vec{E}$.
• Arrows indicate $\vec{E}$ from Y points right, so $\vec{F}$ on X points right.
• X is stationary, confirming electric (not magnetic) interaction, as magnetic force requires motion.

Why A is correct:

• The force on a positive charge follows the electric field direction per $\vec{F} = q\vec{E}$.

Why the others are wrong:

• B: Force direction matches field, not opposes it for positive charge.
• C: Stationary charge experiences no magnetic force; it's electric.
• D: Incorrect field type and wrong direction for positive charge.

Final answer: A