Which sentence would be inappropriate in a piece of research writing with a formal tone?
a: the local spca reports a massive increase in shelter adoptions over the past five years, and executive director robert williams "has every belief that this trend will continue."

b: the number of shelter adoptions in manatee county is rising, and will likely continue in the years to come.

c: last year alone, the manatee county spca found homes for over 500 dogs and cats. the shelter has made it a priority to beat this number in 2014.

d: i've seen a massive increase in shelter adoptions over the past five years, and i have every belief that this trend will continue.