Combination of independent clauses containing quantities

The Zaragoza-Ysleta International Bridge in El Paso, Texas, is one of the 330 ports of entry where customs officials inspect the more than 350 million travelers and 100 million vehicles, trains, and aircraft entering and exiting the U.S. every year.

1. Is the author talking about 100 million as the total combination of vehicles, trains, and aircraft? (A) That is, 100 million == x vehicles + y trains + z aircraft. (B) Or is the author saying there were 100 million vehicles, 100 million trains, and 100 million aircraft?

2. If the answer to (1) is (A), what would be the best way to write (B)?

My thought: (A) seems correct, because the same number of aircraft as the number of vehicles arriving to the same point is unrealistic.

• The statistic is ambiguous twice because trains and aircraft are vehicles. – Matt E. Эллен Dec 13 '11 at 19:03
• @Matt Not in Texas, they aren't! – Kit Z. Fox Dec 13 '11 at 19:06
• @Kitḫ I see. Is this why they wanted independence? – Matt E. Эллен Dec 13 '11 at 19:11
• I expect 100 million is a very loose approximation anyway, and "rubber-tyred" vehicles such as cars and trucks will far outnumber trains and aircraft. So in practice it really doesn't make any difference whether the latter are included - the author would hardly be likely to increase 100 million by the relevant small amount if he intended to include them. – FumbleFingers Dec 13 '11 at 19:17