Final answer:
The ministry of David du Plessis is best characterized by his effective role in introducing the Pentecostal testimony to ecumenical circles, fostering dialogue between different Christian denominations.
Step-by-step explanation:
The statement that best characterizes the ministry of David du Plessis is that he effectively brought the Pentecostal testimony in ecumenical circles. David du Plessis, often known as "Mr. Pentecost," was instrumental in bridging the gap between the Pentecostal movement and mainstream Christianity. His work involved advocating for the Pentecostal movement's inclusion in ecumenical conversations, leading to greater dialogue and understanding between Pentecostal churches and other Christian denominations.