Answer:
The fish is not killed due to the Refraction (bending) of light.
Step-by-step explanation:
The light experiences a phenomenon called Refraction that is the change of path or bending. As light travels from denser medium (water) to a less dense medium (air), its speed increases to some extent. Due to this change in speed of light, the path of the light changes. The observer sees the image of fish in the water formed by these bent rays of light coming off the fish which is at a different location and he/she jabs the spear at that location. However, as it is not the real location of fish but how it appears due to refraction, the spear is jabbed at a wrong location and the fish is not killed.