Directions: Fill in the blanks with the appropriate word.

The winding road was no doubt a _____________ climb and, though at every steep turn the car groaned, we finally reached the top.

The correct answer is 'tortuous' because it means twisting, winding, or complex. The context clues ('winding road', 'steep turn') describe the physical nature of the road. 'Tortuous' is often confused with 'torturous' (painful), but here it correctly describes the road's winding shape. 'Easy', 'fast', and 'slow' don't capture the winding nature.