Answer: The correct sentence is D. Josef walked on the beach, and he also swam in the ocean.
Explanation:<u> D.</u> is the correct sentence because it is <u>the only one who offers a coherent verb tense choice</u>. In other words, <u>D. is the only sentence that conjugates the second verb in the same tense in which the first verb has been conjugated</u>, that is to say the Simple Past Tense. In that way, <u>both verbs ("walked" and "swam") have been conjugated into the Simple Past</u>. In contrast, in the other sentences the verbs do not share the same tense; therefore, they have not been correctly written.