Effect of ideal contraction on Galois correspondent

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This fact is an application of the following pivotal fact/result/idea: nilradical of subring lemma
View other applications of nilradical of subring lemma OR Read a survey article on applying nilradical of subring lemma

Statement

Suppose f:RS is a homomorphism of commutative unital rings, and I is an ideal of S. Suppose Z(I) denotes the subset of Spec(S) comprising the prime ideals which contain I (the Galois correspondent to I under the Galois correspondence between a ring and its spectrum). Then:

Z(Ic)=f*Z(I))¯

An analogous statement is true for the max-spectrum, if we assume that both R and S are Jacobson rings. This is to equate the Jacobson radical with the nilradical.