1.

Do Articles 57 and 71(6) of Directive 2014/24/EU (1) preclude national legislation, such as Article 80(5) of Legislative Decree No 50 of 2016, which requires the exclusion of a tendering economic operator where, during the tendering procedure, a ground is established for excluding a subcontractor forming part of the group of three subcontractors specified in the tender, rather than requiring the tenderer to replace the designated subcontractor?

2.

In the alternative, if the Court of Justice considers that the option of excluding the tenderer is one of the options open to the Member State, does the principle of proportionality enshrined in Article 5 of the EU Treaty, referred to in recital 101 of Directive 2014/24/EU and established as a general principle of EU law by the Court of Justice, preclude national legislation, such as Article 80(5) of Legislative Decree No 50 of 2016, which provides that, where a ground for excluding a designated subcontractor is established during the tendering procedure, a tendering economic operator is to be excluded in all cases, including where there are other subcontractors that have not been excluded and satisfy the requirements for the provision of the services to be subcontracted, or where the tendering economic operator declares that it will not subcontract as it satisfies the requirements for the provision of the services on its own?