Why is reinforcement essential in concrete structures?

Reinforcement is essential in concrete structures primarily because concrete is strong in compression but relatively weak in tension. When loads are applied to a concrete member, such as beams or slabs, tensile stresses can occur, particularly in flexural scenarios. Reinforcement, typically steel bars (rebar) or mesh, is embedded in the concrete to enhance its tensile strength. The combination of concrete's compressive strength and the reinforcement's tensile capacity allows for the construction of safer and more durable structures, capable of withstanding various forces without failing.

The role of reinforcement in providing tensile strength is crucial, as it allows the concrete to resist cracking and structural failure under tension. This makes it indispensable for ensuring that structures can support the expected loads over their service life without compromising integrity. While there are other factors like thermal cracking and load support that reinforcement can indirectly help with, its primary function is to enhance tensile strength, which is why option C is the correct answer.