Answer:
D. Walter Cunningham
Explanation:
Walter Cunningham is one of the prominent astronauts in American History.Although he's already retired,he's currently the chairman of the Texas Aerospace Commission.So,this makes him a Texas scientific leader.
William Philip Gramm (Phil Gramm) is an American economist and politician who represented Texas in both houses of Congress.Though he began his political career as a Democrat,Gramm switched to the Republican Party in 1983.
Dr. Michael Ellis Debakey was a Lebanese-American cardiac surgeon and vascular surgeon,scientist and medical educator who became the chancellor emeritus of Baylor College of Medicine in Houston,Texas.
Samuel Taliaferro Rayburn was an American politician who served as the 43rd speaker of the United States House of Representatives.He was a 25-term congressmen,representing Texas's 4th congressional district as a Democrat from 1913 to 1961.
