N10-004单项选择题每日一练(2019.01.14)

单项选择题
Which of the following attacks occurs when a hijacker intercepts traffic, modifies it, then sends thetraffic?（）
A.DoS
B.Smurf
C.Man-in-the-middle
D.Phishing
单项选择题
Which of the following is true about an IP address if the first bit is a zero?（）
A. The address is a Class A address.
B. The address is a Class B address.
C. The address is a Class C address.
D. The address is a Class D address.
单项选择题
A technician wants to use an existing DHCP server for three additional VLANs. Which of the following features needs to be configured to allow for this addition?（）
A. DHCP server
B. Proxy server
C. Repeater
D. DHCP relay
单项选择题
When debugging a routing problem, the time-to-live (TTL) value can be used to determine:（）
A. Number of routes available.
B. Number of router hops.
C. Time that an advertised route is valid.
D. Time to make a round trip.
单项选择题
A technician receives an urgent call that the switch in accounting is down. Which of the followingshould the technician do FIRST to troubleshoot this issue?（）
A. Identity symptoms and problems
B. Document the process and solutions
C. Establish the most probable cause
D. Escalate if necessary.