I can't change the low B string on my bass, so I'm forced to buy just a 4 string set. My B string is .125

Should I go for
a) 050-070-085-105
b) 045-065-085-105

I like thicker gauge stings, but I think the 50s and 70s might not fit into the mix with the others, because the matching B-string for this set would be .135

Wait, why can't you change your B string? You need a thicker B than that anyway.

Really, it depends on your playing style and preferences. What's the gauge of the strings you're using now? How do you like them? That should answer your question.
Millie, my Peavey Grind Fiver
Peavey BAM 210 350w combo amp
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Modded Ernie Ball VP Jr.
Monster Bass Cable, 21'

Quote by NakedBassist
Welcome to bass, you'll f*cking love it
What gauge do you usually use?

If its standard which I will assume it is, not entirely sure tho then go for the 45's.

I prefer thinner well.. standard D/Gs namely 45s and 65s but I have used thinner gauges which I didn't like and well thicker gauges I find too muddy.

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