Question 1

To gradually develop

In the context provided, 'evolved' refers to the gradual development of systems within the body, particularly the cardiovascular system, to maintain essential functions such as blood pressure regulation.

A) To spread

This option is incorrect as 'to spread' implies a physical distribution or expansion, which does not capture the essence of 'evolved' in terms of development or adaptation over time. The context emphasizes the progression and sophistication of physiological systems rather than mere dispersion.

B) To gradually develop

This option is correct as it accurately reflects the meaning of 'evolved' in the context of the body's systems adapting and improving over time to meet the demands of maintaining homeostasis, specifically in blood pressure regulation. The passage discusses how the cardiovascular system has diversified and matured, which aligns perfectly with this definition.

C) To revolve

This choice is incorrect because 'to revolve' suggests circular movement around a point, which does not relate to the concept of development or improvement inherent in 'evolved'. The context focuses on the maturation of systems rather than any physical rotation.

D) To shift

This option does not accurately represent the term 'evolved' as 'to shift' implies a change in position or direction rather than a gradual development over time. The passage indicates a more complex process of adaptation rather than simple movement.

Conclusion

The term 'evolved' in the provided context means 'to gradually develop', as it reflects how biological systems have adapted and refined their functions over time to maintain vital processes like blood pressure regulation. All other options fail to capture this nuanced meaning, focusing instead on movement or distribution, which does not align with the intended concept of biological evolution.