、。
Amid all this, the field that has made the most rapid progress is IT.
Literal
That-kind-of-amid-で rapid progress [object-を] accomplish-come [nominalizer-のが], IT [copula-である].
Formal expository writing. The cleft construction [clause]+のが+[X]+である focuses on the IT industry as the answer to 'what made rapid progress?' のが is the focusing version of の (the nominalizer); compare のは (topical) vs のが (focusing). 遂げる ('to accomplish, achieve') is a literary verb. ~てくる here marks development continuing up to the present. Typical of business journalism and academic writing.