What problem can you imagine coming from using digitized
DNA storage?

There are many problems associated with digitized DNA storage.

Explanation:

The cost of encoding the DNA data is high and lot of working efficiency is required for the same. The encoding process requires a considerable amount of time and encoding is slow. It takes about 400 bytes per second. This is done in a silicon memory chip. The process is millions of times slower.

adding a(n) to an electric circuit would increase the magnetic field around a wire;

b. solenoid

a solenoid is a type of electromagnet whose purpose is to generate a controlled magnetic field.

if the purpose of the solenoid is instead to impede changes in the electric current, a solenoid can be more specifically classified as an inductor rather than an electromagnet.