Question

Which sentence correctly links two independent clauses?

The packing box had been used and reused; a heavy layer of packing tape was all that held it together.
The packing box had been used and reused, a heavy layer of packing tape was all that held it together.
The packing box had been used and reused and a heavy layer of packing tape was all that held it together.
The packing box had been used and reused now a heavy layer of packing tape was all that held it together.

I've ruled out C and D.
I kind of think it's A