请教一道逻辑题

For a local government to outlaw all strikes by its workers is a costly mistake, because all its labor disputes must then be settled by binding arbitration, without any negotiated public-sector labor settlements guiding the arbitrators. Strikes should be outlawed only for categories of public-sector workers for whose services no acceptable substitute exists.

The statement above best suport which of the following conclusions?

a) Where public-service workers are permitted to strike, contract negotiations with those workers are typically settled without a strike.

b) Where strikes by all categories of public-sector workers are outlawed, no acceptable substitutes for the services provided by any of those workers are avaiable.

c) Bindng arbitration tends to be more advantageous for public-service workers when it is the only available means of settling labor disputes with such workers.

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谢谢。