Which statement would be the best final sentence in a conclusion on the topic of sand filter maintenance

"Over time the sand bed will become plugged with dirt and require a cleaning process known as backwashing."  is the most reasonable because this statement shows closure to the paragraph by notifying the reader the filter will need to be cleaned out. It also makes a good transition to start the following paragraph explaining backwashing.

- "a.) it includes letters and books gathered over 1200 years, and consists of two parts.

- most of the new testament is letters from paul to the different churches, and since there's a new testament that means there is an old testament. "

grunge