Since $l_1$ and $l_2$ are parallel, we know the following:
a = c = e = g
b = d = f = h

So, we have:
Quantity A: a + f + g
Quantity B: b + e + h

Since b = f and since a = g, we can rewrite Quantity A as follows:
Quantity A: a + b + a = 2a + b

Since b = e and since a = e, we can rewrite Quantity B as follows:
Quantity B: b + a + b = 2b + a

So, we have:
Quantity A: 2a + b
Quantity B: 2b + a

Subtract a from both quantities, and subtract b from both quantities to get:
Quantity A: a
Quantity B: b

Since angles a and b lie on the same line, we know that a + b = 180
We're told that a > 90, which means b < 90 (in order for a and b to add to 180)

Answer: A

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