Off topic:aligning using bowtie2?

Question

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I am doing aligning with bowtie2 and just need reads that aligned exactly 1 time. so I have performed 2 ways: but I am not sure whether the first one is correct or not, while most of literature used the second one?

1= bowtie2 --very-sensitive --score-min C,0,0 --> that number of aligned exactly 1 times increased but the overall aligning decreased.

2= bowtie2 --very-sensitive --> that number of aligned exactly 1 times are less than first way but the overall aligning is higher.