The concordat of worms:

(a) demanded henry iv resign as holy roman emperor.
(b) forced gregory vii to abandon rome.
(c) stipulated that lay rulers could no longer invest prelates with the symbols of their office.
(d) excommunicated the holy roman emperor.
(e) prevented the presence of the emperor or his representative at elections of imperial bishops and abbots.

Option-(c): Is the best option to choose from the given five options.

Explanation:

The Concordat of Worms:

It was an agreement between the Henry IV and the  pope. It was due to the conflicts between the two, as there was a conflict between them over the Church. As they had tensions over the power of church. And they eventually got to a point where they resolved the whole problem.

As they stipulated that lay rulers could no longer invest prelates with the symbols of their office.

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