The answer is A because all the others are wrong. You are saying that Marcos was studying when I arrived at his house.
¡ No puedo entender las matemáticas !
Answer:
1) Cuya
2) Cuando
3) Que
Explanation:
1. cuya ( whose) ...company dedicates to...
2. cuando (when) ... the water contaminates, there are many toxic substances.
3. que ( that) ... looks for a solution for the energy consumption , makes studies in Chicacaque...
