The listener is bound to IP address 10.0.0.50 on port 8200, so the client must target that address, not localhost. The configuration also sets tls_disable = true, which means the listener is using plain HTTP rather than HTTPS. Therefore, the correct VAULT_ADDR value is http://10.0.0.50:8200. Option A uses the correct IP and port but the wrong protocol because TLS is disabled. Options B and C target 127.0.0.1, which would only work for a Vault listener bound locally on the client machine. Vault assumes TLS by default unless explicitly disabled, so when TLS is disabled, the scheme must be http://.

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