Which of the following statements regarding LSPs are true?

IGP-based LSPs are established solely from information contained in routing tables.

The constraint-based routed LSP is calculated at the ingress of the network, based on the router database and user defined constraints.

The constraint-based routed LSP is calculated at each hop of the LSP, based on the route table and user defined constraints.

IGP-based LSPs must use LDP signaling.