The correct answer is B) build more missions and presidios in Texas.
The Spanish action in response to the French threat to East Texas was to build more missions and presidios in Texas.
Spanish General Alonso de León explored the East part of Texas, then occupied by people called Caddoes. León used the name Tejans to identify them. He reported to the Viceroy of Spain that these new lands had many raw materials and natural resources that would be of great benefit for the Spanish crow, he also believed that the frays could evangelize the Coddoes. When the French threatened to invade Texas, the Spanish build missions such as the mission Santísimo Nombre de María or San Franciso de las Tejas.