Explanation:

- Her parents always encouraged her in her studies.

- This is the correct option. To encourage means to give support, confidence, and hope. Parents often motivate and support their children's educational pursuits.

- Her parents always interested her in her studies.

- This is incorrect. "Interested" implies causing someone to be interested, which is not quite appropriate in this context. Parents are more likely to support rather than create interest.

- Her parents always impressed her in her studies.

- This is incorrect. "Impressed" means to have a strong, often favorable effect on someone's feelings. It's more about admiration, not direct support in studies.

- Her parents always expected her in her studies.

- This is incorrect. "Expected" refers to anticipation or belief that something will happen. It doesn't fit as neatly for direct help or support in studies.