What do mean by marginalization?

Which sentence contains a comma splice? marco rode to school on his bicycle this morning, he arrived an hour early.marco, who enjoys riding his bicycle to school, arrived just before the bell today.marco rode to school on his bicycle on monday, tuesday, and wednesday.marco, who rode to school on his bicycle this morning, arrived an hour early.mark this and returnsave and exit

What should i say so i can switch my instrument

(i think my answer is a, am i correct? ) a pentagonal traffic sign is a sign. a. school crossing b. parking c. wrong way d. yield