Which parts of this excerpt from beowulf relate to a warrior code?
beowulf answered, ecgtheow's son:
"grieve not, o wise one! for each it is better,
his friend to avenge than with vehemence wail him;
each of us must the end-day abide of
his earthly existence; who is able accomplish

glory ere death! to battle-thane noble
lifeless lying, 'tis at last most fitting.
arise, o king, quick let us hasten
to look at the footprint of the kinsman of grendel!
i promise thee this now: to his place he’ll escape not, . ."

Based on the given excerpt above taken from "Beowulf", an Epic poem, the part that shows a warrior code is the second part: 
Glory ere death! To battle-thane noble
Lifeless lying, 'tis at last most fitting.
Arise, O king, quick let us hasten
To look at the footprint of the kinsman of Grendel!
I promise thee this now: to his place he’ll escape not, . . ."
When we say warrior code, in Beowulf, this refers to the code between the thanes and their Lord. What the thanes do is that they provide their Lord with protection and loyalty, and in exchange, the lord provides their needs.

The part of "Beowulf" text that resembles a warrior code is the line "Glory ere death! To battle-thane noble."

We can arrive at this answer because:

The warrior code stressed the importance of battles.Furthermore, these codes showed how honor, glory, and success resulted in those who engaged in battles with bravery and strength.Therefore, the code stated that warriors should not fear the moment to fight if they had made their names with honor.Not even death should be feared, as it was better to die an honorable warrior than an honorless coward.

We can see that the first line of the second stanza of the text, shown in the question above, shows the central idea of the warrior code by showing that honor was what the warrior had of most value and that it would be a reason for pride to die in an honorable way.

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The answer should be d.