Which expression is equivalent to 1a+1b+1c\frac{1}{a} + \frac{1}{b} + \frac{1}{c}a1+b1+c1?
a+b+cabc\frac{a+b+c}{abc}abca+b+c
bc+ac+ababc\frac{bc+ac+ab}{abc}abcbc+ac+ab
1a+b+c\frac{1}{a+b+c}a+b+c1
abcab+bc+ac\frac{abc}{ab+bc+ac}ab+bc+acabc