What is the term for the bending of light caused by a black hole's strong gravity?

• A. Gravitational lensing
• B. Doppler shift
• C. Hawking radiation
• D. Cosmic inflation

Answer: (A)

Light bending by a massive object follows the path of light as it travels through curved spacetime. This effect, seen when a black hole’s gravity is strong enough, is known as gravitational lensing. The gravity acts like a lens, altering the light’s trajectory so background sources can appear distorted, brighter, or even as multiple images or rings when the alignment is right. This phenomenon lets astronomers detect and measure black holes and study distant objects that would otherwise be hidden or faint.

Other terms describe different ideas: Doppler shift is a change in light’s color due to motion toward or away from us, not bending. Hawking radiation is hypothetical emission from quantum effects near a black hole’s horizon, not about light paths. Cosmic inflation is the rapid expansion of space in the early universe, which isn’t about light bending near black holes. So the bending of light caused by a black hole’s strong gravity is gravitational lensing.