Excerpt from Marco Polo Part 1
John H. Haaren

When he was about twenty-one Kublai Khan sent him on business to a distant part of China. He did the work and from that time was often employed as an envoy of the Chinese monarch. His travels were sometimes in lands never before visited by Europeans and he had many strange adventures the almost unknown tribes of Asia. Step by step he was promoted. For several years he governor of a great Chinese city.

His travels were sometimes in lands never before visited by Europeans and he had many strange adventures with the almost unknown tribes of Asia.

Which correctly links the independent clauses in this compound sentence from section 7?
A) His travels were sometimes in lands never before visited by Europeans; he had many unique adventures with the almost unknown tribes of Asia.
B) His travels were sometimes in lands never before visited by Europeans; so he had many unique adventures with the almost unknown tribes of Asia.
C) His travels were sometimes in lands never before visited by Europeans: so he had many unique adventures, with the almost unknown tribes of Asia.
D) His travels were sometimes in lands never before visited by Europeans, so, he had, many unique adventures with the almost unknown tribes of Asia.