It is custom of Christianity to sing morning prayer in the church regularly.

The correct answer is B. Matin.

Matin is a service of Christian worship that is traditionally held in the morning. It is a time for Christians to pray, sing hymns, and read Scripture. Matin is often followed by a sermon.

The other options are incorrect.

• Epilogue is a speech or writing that comes at the end of something.
• Epitaph is an inscription on a tomb or monument.
• Vesper is a service of Christian worship that is traditionally held in the evening.