男性，65岁，乏力伴食欲减退半年余，体重下降约15kg，黑便，突然呕吐暗红色血液，量约400ml。查体：腹平，剑突下轻压痛，肝脾未触及，移动性浊音阴性。此患者应怀疑诊断为()
A. 食管静脉曲张破裂出血
B. 胃癌出血
C. 慢性萎缩性胃炎
D. 应激性溃疡出血
E. 消化性溃疡出血
What are two recommended ways of protecting network device configuration files from outside network security threats? (Choose two.)（）
Allow unrestricted access to the console or VTY ports.
B. Use a firewall to restrict access from the outside to the network devices.
C. Always use Telnet to access the device command line because its data is automatically encrypted.
D. Use SSH or another encrypted and authenticated transport to access device configurations.
E. Prevent the loss of passwords by disabling password encryption.&e
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